The art of pre-bolusing insulin

A note of caution: Always talk to your doctor before making changes to your insulin regiment.

For the uninitiated, I’ll let you in on a secret. Pre-bolusing insulin is key to preventing post-mealtime spikes in blood sugar. So what is pre-bolusing? It simply means that you inject your insulin in advance before eating by up to forty minutes. This gives it enough time to hit the bloodstream and take better care of the carbs in the food.

When to inject is individual and also depends on temperature, hormonal state of the day, and the other three million factors that affect diabetes parameters. It helps to be a bit boring and eat a lot of the same things if you want good diabetes control.

I first came across pre-bolusing when I started using short-acting (regular) insulin on the Bernstein protocol. Short-acting insulins, such as Humulin R and ActRapid, have a different profile curve than fast-acting insulin like NovoRapid, and need to be taken in advance when you’re eating carbs. Regular is ideal to take when you eat almost no carbs and depend on gluconeogenesis for glucose, as it follows the slow release from protein. 

Without getting too technical I started to experiment with pre-bolusing NovoRapid, and found that I could increase the carb count from twenty to sixty grams a day. It might not sound like a lot but to a diabetic, that’s a world of difference. Forbidden foods such as potatoes, root vegetables, and fruit were suddenly back on the menu. 

Note that I don’t eat big meals, and I never have more than 30g of carbs in one sitting. That’s 100g of potatoes and a tiny side salad. I use a lot of fat in my meals, which slows down digestion and is important to prevent spikes. Small insulin doses are still key, but it is possible to eat high GI foods providing the serving is small and you pre-bolus fast-acting insulin. Portion control is as important as carb count in diabetes, and you can not wiggle massive insulin doses if stable blood sugar is your goal.

For breakfast I eat no carbs at all. Mornings are rough enough without having to deal with mathematical equations.